In-vehicle light apparatus

ABSTRACT

A light apparatus mounted on a vehicle includes a lamp that emits light into a first region through a first cover and a radar provided on a lower side or an upper side of the lamp. The radar includes a separator provided between the lamp and the radar, a circuit board having a board surface arranged in a substantially horizontal manner, and an antenna that is disposed on the board surface of the circuit board, transmits electromagnetic waves through a second cover in a second region that is at least partially different from the first region, and receives reflected waves through the second cover from objects outside the vehicle in the second region.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of U.S. patentapplication Ser. No. 17/202,670 filed Mar. 16, 2021, which is acontinuation of U.S. patent application Ser. No. 16/926,320 filed Jul.10, 2020 (now U.S. patent application Ser. No. 10,981,491 issued Apr.20, 2021), which is a continuation application of U.S. patentapplication Ser. No. 16/585,061 filed Sep. 27, 2019 (now U.S. patentapplication Ser. No. 10,744,926 issued Aug. 18, 2020), which claims thebenefit of Japanese Patent Application Numbers 2018-183699 filed Sep.28, 2018, 2018-183702 filed Sep. 28, 2018, 2018-183711 filed Sep. 28,2018, and 2018-183715 filed Sep. 28, 2018. The disclosures of eachapplication are expressly incorporated herein by reference in theirentireties.

TECHNICAL FIELD

The present disclosure relates to an in-vehicle light apparatus.

BACKGROUND ART

In the related art, an in-vehicle light apparatus provided with amillimeter wave radar (hereinafter, referred to as “radar apparatus”)integrally with a lamp (for example, a headlight or a backlight) forirradiating outside the vehicle is known (for example, see PTL1).

Such an in-vehicle light apparatus is suitable for saving a space forinstalling the millimeter wave radar and improving the design of thevehicle body.

CITATION LIST Patent Literature PTL 1

-   Japanese Patent Application Laid-Open No. 2008-186741

SUMMARY OF INVENTION

The present disclosure which solves the problems mentioned above is anin-vehicle light apparatus for monitoring a region in a first directionoutside a vehicle, the in-vehicle light apparatus including:

a lamp unit including: a light source that emits light in the firstdirection; and a reflector surrounding the light source; and

radar unit provided on a lower side or an upper side of the lamp unit,the radar unit including: a circuit board disposed such that a boardsurface extends substantially along a horizontal direction; and aplurality of antenna elements disposed in the board surface of thecircuit board to transmit an electromagnetic wave in the first directionand to receive a reflected wave thereof,

in which the plurality of antenna elements are arranged in an array on aside of the first direction relative to the reflector in plan view, and

an array direction of the plurality of antenna elements is a directionintersecting the first direction and non-parallel to an extendingdirection of an end portion on the side of the first direction of thereflector in plan view.

According to an in-vehicle light apparatus according to an example ofthe present disclosure, it is possible to suppress deterioration ofradar performance caused by multiple reflections with an integratedradar and lamp configuration.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a perspective view illustrating a state of installation of alight apparatus in a vehicle according to Embodiment 1;

FIG. 1B is a plan view illustrating the state of installation of thelight apparatus in the vehicle according to Embodiment 1;

FIG. 1C is a front view illustrating the state of installation of thelight apparatus in the vehicle according to Embodiment 1;

FIG. 2 is a sectional side view illustrating an example of aconfiguration of the light apparatus according to Embodiment 1;

FIG. 3 is a plan view illustrating a positional relationship of a radarunit and a lamp unit of the light apparatus according to Embodiment 1;

FIG. 4 is an upper perspective view illustrating a positionalrelationship of a radar unit and a lamp unit of the light apparatusaccording to Embodiment 1;

FIG. 5A is a drawing illustrating a position of installation of anantenna in a light apparatus according to Modification 1;

FIG. 5B is a drawing illustrating a position of installation of theantenna in the light apparatus according to Modification 2;

FIG. 6 is a general drawing illustrating an example of a configurationof a light apparatus according to Embodiment 2;

FIG. 7 is a sectional side view illustrating an example of aconfiguration of the light apparatus according to Embodiment 2;

FIG. 8 is a perspective view illustrating an example of a configurationof a garnish material according to Embodiment 2;

FIG. 9 is a plan view of a radar unit according to Embodiment 2 viewedfrom above;

FIG. 10A is a perspective view illustrating a state of installation of alight apparatus in a vehicle according to Embodiment 3;

FIG. 10B is a plan view illustrating the state of installation of thelight apparatus in the vehicle according to Embodiment 3;

FIG. 10C is a front view illustrating the state of installation of thelight apparatus in the vehicle according to Embodiment 3;

FIG. 11 is a sectional side view illustrating an example of aconfiguration of the light apparatus according to Embodiment 3;

FIG. 12 is a plan view of a radar unit according to Embodiment 3 viewedfrom above;

FIG. 13 is a plan view illustrating a positional relationship of a radarunit and a lamp unit of the light apparatus according to Embodiment 3;

FIG. 14 is an upper perspective view illustrating a positionalrelationship of a radar unit and a lamp unit of the light apparatusaccording to Embodiment 3;

FIG. 15 is a sectional side view illustrating an example of aconfiguration of the light apparatus according to Embodiment 4;

FIG. 16 is a sectional side view illustrating an example of aconfiguration of the light apparatus according to Embodiment 5;

FIG. 17 is a sectional side view illustrating an example of aconfiguration of the light apparatus according to Embodiment 6;

FIG. 18 is a sectional side view illustrating an example of aconfiguration of the light apparatus according to Embodiment 7;

FIG. 19 is a perspective view illustrating a state of installation of anin-vehicle light apparatus in a vehicle according to Embodiment 8;

FIG. 20 is a sectional side view illustrating an example of aconfiguration of the in-vehicle light apparatus according to Embodiment8;

FIG. 21 is a plan view of a radar apparatus according to Embodiment 8viewed from above;

FIG. 22 is a block diagram illustrating an example of a configuration ofan ECU according to Embodiment 8;

FIG. 23 illustrates the behavior of the reflected wave when ice, snow orthe like is attached to a front face of a cover member;

FIG. 24 illustrates a flowchart illustrating an example of an operationof the ECU according to Embodiment 8;

FIG. 25 is a perspective view illustrating a state of installation in avehicle of an antenna apparatus according to Embodiment 9;

FIG. 26 is a sectional side view illustrating an example of aconfiguration of an antenna apparatus according to Embodiment 9;

FIG. 27 is a plan view of antenna apparatus according to Embodiment 9viewed from above;

FIG. 28 is an enlarged view illustrating a front face of a dielectriclens according to Embodiment 9;

FIG. 29 is an enlarged view illustrating the front face of thedielectric lens according to Embodiment 9;

FIG. 30 is a diagram illustrating the relationship between the size andthe reflectance (S11) of a protrusion;

FIG. 31 is a diagram illustrating a relationship between the size of theprotrusion and an antenna gain of the antenna;

FIG. 32 is a sectional side view illustrating an example of theconfiguration of the antenna apparatus according to Embodiment 10; and

FIG. 33 is a sectional side view illustrating an example of theconfiguration of the antenna apparatus according to Embodiment 11.

DESCRIPTION OF EMBODIMENTS

In the following, preferred embodiments of one example of the presentdisclosure will be described in detail with reference to theaccompanying drawings. In the present specification and drawings,components having substantially the same function are denoted by thesame reference numerals, and redundant description will be omitted.

Embodiment 1

In an in-vehicle light apparatus of the related art, a radar apparatusand a reflector of a lamp (a reflective member configured to condense alight emitted from a light source and adjust an irradiation range of thelight) are placed close to each other. Therefore, in this type ofin-vehicle light apparatus, the electromagnetic wave transmitted fromthe radar apparatus and reflected by and returned from the target may bere-reflected by the reflector and arrive at the antenna of the radarapparatus.

In particular, the reflector reflects not only the light emitted fromthe light source but also radio waves used in radar apparatus and thelike. The reflector is a reflective member with a wide planar area, butwhen the radar apparatus and the reflector are placed close to eachother, the reflection at the end of the reflector has the greatesteffect. This may cause multiple reflections to and from the radarapparatus and the like where the antenna is disposed, which may generatestanding waves between itself and the antenna. The standing wave causesfading of an electromagnetic wave arriving at the antenna, and thetarget detection performance is degraded in the receptioncharacteristics of the antenna.

In view of the above-mentioned problems, an example of the presentdisclosure provides an in-vehicle light apparatus capable of suppressingdeterioration of radar performance due to multiple reflections whileintegrating a radar apparatus and a lamp.

Hereinafter, referring to FIG. 1A, FIG. 1B, FIG. 1C, FIG. 2, FIG. 3 andFIG. 4, an example of the configuration of the in-vehicle lightapparatus according to Embodiment 1 (hereinafter abbreviated as “lightapparatus”) will be described. The light apparatus according toEmbodiment 1 is applied to a headlight configured to illuminate thefront of the vehicle. Note that only the configuration of a headlight onthe right front of the vehicle will be described.

In each drawing, in order to clarify the positional relationship in eachconfiguration, a common orthogonal coordinate system (X, Y, Z) isillustrated with reference to a forward direction in which the radarapparatus (corresponding to a radar unit of the present disclosure)transmits the electromagnetic wave to the outside the apparatus (thatis, the direction of detection of an object). In the followingdescription, a plus direction of the X-axis represents the forward inwhich the radar apparatus transmits an electromagnetic wave to theoutside the apparatus (hereinafter referred to as “forward direction” or“first direction”), a plus direction of the Y-axis represents the leftside of the radar apparatus (hereinafter abbreviated as “leftwarddirection”) and a plus direction of the Z-axis represents upward ofradar apparatus (hereinafter abbreviated as “upward direction”).

In the following description, +Z direction corresponds to the upward ofthe vehicle, and a direction about 30 degrees in the +Y direction from+X direction corresponds to the direction of travel of the vehicle.

FIG. 1A is a perspective view illustrating a state of installation inthe vehicle of light apparatus U1 according to Embodiment 1. FIG. 1B isa plan view illustrating a state of installation in the vehicle of lightapparatus U1 according to Embodiment 1. FIG. 1C is a front viewillustrating a state of installation in the vehicle of light apparatusU1 according to Embodiment 1.

Light apparatus U1 according to Embodiment 1 includes radar unit 10,lamp units 20 a, 20 b, and 20 c, and housing 30.

In light apparatus U1 according to this embodiment, three lamp units 20a, 20 b, and 20 c are arranged adjacent along the left-right direction,and radar unit 10 is disposed on a lower side of lamp units 20 a, 20 b,and 20 c.

Radar unit 10 according to Embodiment 1 transmits an electromagneticwave obliquely rightward (+X direction) with respect to the direction oftravel of the vehicle, and performs detection of an object present inthe corresponding direction. Then, a radar unit (not illustrated) builtin the left headlight performs detection of an object present obliquelyleftward with respect to the direction of travel of the vehicle.

FIG. 2 is a sectional side view of light apparatus U1 according to thisembodiment. FIG. 3 is a plan view illustrating a positional relationshipbetween radar unit 10 and lamp units 20 a, 20 b, and 20 c of lightapparatus U1 according to Embodiment 1. FIG. 4 is an upper perspectiveview illustrating the positional relationship between radar unit 10 andlamp units 20 a, 20 b, and 20 c of light apparatus U1 according toEmbodiment 1.

Housing 30 forms a storage space in the front end region of the vehicle,and stores radar unit 10 and lamp units 20 a, 20 b, and 20 c in thestorage space. Housing 30 also has front cover 30 a configured to coverthe front face of the storage space. Housing 30 is made of, for example,a resin material (for example, polycarbonate and the like). Front cover30 a is made of, for example, a resin material having transparency tolight (for example, polycarbonate and the like).

Lamp unit 20 a includes light source 21 a and reflector 22 a.

Light source 21 a is, for example, an LED lamp or an incandescent lamp,and emits light toward the front (in this case, a direction about 30degrees to the -Y direction from +X direction). Light source 21 a isattached to a rear side wall of housing 30. Note that a light sourcehaving a condensing lens may be used as light source 21 a.

Reflector 22 a is disposed so as to surround the periphery of lightsource 21 a, collects light emitted from light source 21 a, and adjustsan irradiation range of light. Reflector 22 a is formed of, for example,a quadrangular pyramid-shaped cylindrical member having an openingdirected toward the front side and increasing in opening diameter towardthe front side. Reflector 22 a is formed of a metal member such as analuminum material, for example. Reflector 22 a may be formed bymetallizing a resin member.

Lamp units 20 b and 20 c have the same configuration as lamp unit 20 a,and are made up of light sources 21 b and 21 c and reflectors 22 b and22 c surrounding light sources 21 b and 21 c, respectively. Lamp units20 a, 20 b, and 20 c are equipped with a system that automaticallyshifts the headlight irradiation area, for example, called an adaptivehigh beam system.

Hereinafter, any one of lamp unit 20 a, lamp unit 20 b, and lamp unit 20c is abbreviated as “lamp unit 20”, “light source 21”, and “reflector22” unless particularly distinguished.

Radar unit 10 includes circuit board 11, antenna 12, and signalprocessing IC 13.

Circuit board 11 is a board on which antenna 12 and signal processing IC13 are mounted. As circuit board 11, for example, a Printed CircuitBoard (PCB) substrate, a semiconductor substrate with built-in signalprocessing IC 13, or the like is used.

In view of miniaturization of light apparatus U1, circuit board 11 isdisposed on the lower side of reflector 22 such that the board surfaceextends substantially along the horizontal direction. Here,“substantially along the horizontal direction” includes not only a statein which the board surface is completely horizontal to the ground butalso a state in which the board surface is inclined with respect to theground. Circuit board 11 may be disposed on the upper side of reflector22.

In other words, radar unit 10 constitutes a horizontal type millimeterwave radar in which circuit board 11 is disposed horizontally. As aresult, radar unit 10 is thinner than lamp unit 20 in the ±Z directions.

Antenna 12 is disposed in the front area of the board surface of circuitboard 11 and transmits electromagnetic wave Ft forward (+X direction),and receives reflected wave Fr which is the electromagnetic wavereflected by a target.

Antenna 12 comprises, for example, an end-fire array antenna havingdirectional characteristics in the direction of the front end side ofcircuit board 11. The end-fire array antenna is configured to include aplurality of strip conductors which are arranged such that thelongitudinal direction thereof are in parallel, and transmits andreceives electromagnetic waves along the direction in which theplurality of strip conductors are arranged.

Antenna 12 is composed of, for example, six end-fire array antennas(hereinafter also referred to as “antenna elements”) 12 a arranged in anarray along ±Y direction. Antenna 12 is formed as a phased array antennaby six antenna elements 12 a.

For example, signal processing IC 13 sends a high-frequency drive signalto antenna 12 to transmit an electromagnetic wave (for example, anelectromagnetic wave in the millimeter wave band) from antenna 12, orperforms reception processing for a received signal relating to areflected wave received by antenna 12. Then, reception processing (forexample, detection wave processing or frequency analysis processing) bysignal processing IC 13 is performed to detect the distance to thetarget (for example, a vehicle or a person), the azimuth where thetarget is present, and other parameters such as the reflection intensityand speed of the target. Here, since the reception processing by signalprocessing IC 13 is the same as that of a known configuration, detaileddescription thereof is omitted here.

Radar unit 10 according to Embodiment 1 is configured to be housed inthe same housing 30 as lamp unit 20, but may be housed in a radarhousing separate from housing 30 and attached to housing 30. Further, aconfiguration in which a resin separator or the like is present betweenradar unit 10 and lamp unit 20 is also applicable.

Here, the details of the position of installation of antenna 12 in lightapparatus U1 according to Embodiment 1 will be described with referenceto FIG. 3 and FIG. 4.

Normally, the reflected wave transmitted from antenna 12 and reflectedback by target arrives not only at the position of installation ofantenna 12 but also at various positions around antenna 12. At thistime, since reflector 22 is made of metal members, the reflected wavearriving at reflector 22 is re-reflected by reflector 22 and travels invarious directions (hereinafter referred to as multiple reflectedcomponents of reflected waves”). In particular, the re-reflection occursat front end portions 22 aa, 22 ba and 22 c a of reflector 22.

Here, if the reflecting surface of reflector 22 and the board surface ofcircuit board 11 on which antenna 12 is disposed face each other, themultiple reflected components of the reflected wave will cause astanding wave between reflector 22 and antenna 12. Then, the standingwave is superimposed on the reflected wave that directly arrives atantenna 12 from the target, and a blind spot area in which the targetcannot be detected is generated in the reception characteristics ofantenna 12.

From such a point of view, antenna 12 according to Embodiment 1 isdisposed on the front side (that is, the vehicle external side) relativeto reflector 22. In other words, antenna 12 is arranged so as not tooverlap with reflector 22 in plan view.

This prevents antenna 12 and reflector 22 from facing each other,thereby preventing the generation of the standing wave between antenna12 and reflector 22.

In addition, the array direction of the plurality of antenna elements 12a, which constitutes antenna 12 of Embodiment 1 is a direction not inparallel to the extending direction of front end portions 22 aa, 22 ba,and 22 ca of reflector 22 and intersecting a forward direction (±Ydirection) in plan view. More preferably, the array direction of antenna12 is set to have an angle ranging from 9 degrees to 171 degrees (angleθ in FIG. 3) with respect to the extending direction of front endportions 22 aa, 22 ba and 22 ca of reflector 22 in plan view.

This makes it possible to reflect the reflected waves reaching the frontend portions 22 aa, 22 ba and 22 ca of reflector 22 so as to be directedtoward the positive +Y direction or −Y direction, so that the reflectedwaves can be diffused away from the position of installation of antenna12. In other words, it is possible to suppress the amount of themultiple reflected components of the reflected waves arriving at antenna12.

The positional relationship between antenna 12 and reflector 22 is setsuch that, in a region in which circuit board 11 and reflector 22overlap with each other in plan view, a position where the contourformed by front end portions 22 aa, 22 ba, and 22 ca of reflector 22 isforwardly convex (the position of an edge portion 22 bb of reflector 22b in FIG. 3) is closer to a central position of elements group of theplurality of antenna elements 12 a (a position near third antennaelement 12 a from left most antenna element 12 a among six antennaelements 12 a in FIG. 3) than a position where the contour formed byfront end portions 22 aa, 22 ba, and 22 ca of reflector 22 is forwardlyconcave (positions of edge portions 22 cb and 22 bc of the reflector 22b in FIG. 3).

This makes the reflected waves arriving at front end portions 22 aa, 22ba and 22 c a of reflector 22 are diffused away from a position ofinstallation of antenna 12 (in +Y direction or −Y direction here) whenre-reflecting at front end portions 22 aa, 22 ba and 22 c a of reflector22. Reflected waves arriving at front end portions 22 aa, 22 ba, and 22ca of reflector 22 are reflected toward +Y direction or −Y direction,and the reflected waves are prevented from arriving at antenna 12.

ADVANTAGEOUS EFFECT OF ONE EXAMPLE

As described above, in-vehicle light apparatus U1 according to theEmbodiment 1 includes lamp unit 20, including light source 21 configuredto emit light to the front (first direction), reflector 22 surroundinglight source 21, and radar unit 10 including circuit board 11 disposedon a lower side or an upper side of lamp unit 20 with the board surfaceextending horizontally, and a plurality of antenna elements 12 adisposed in the board surface of circuit board 11 so as to transmit andreceive electromagnetic waves to and from a region in the firstdirection. Further, the plurality of antenna elements 12 a are arrangedin an array in front of reflector 22 in plan view, the array directionof the plurality of antenna elements 12 a is a direction intersectingthe first direction and non-parallel to the extending direction of frontend portions 22 aa, 22 ba, and 22 ca of reflector 22 in plan view.

Accordingly, according to in-vehicle light apparatus U1 of Embodiment 1,the occurrence of a standing wave between reflector 22 and the portionof antenna 12 of circuit board 11 due to electromagnetic waves (multiplereflected components of the reflected wave) re-reflected by reflector 22among the reflected waves from the target can be suppressed. This makesit possible to suppress the situation in which the multiple reflectedcomponents of the reflected waves are superimposed on the reflectedwaves coming directly from the target to antenna 12, therebydeteriorating the reception characteristics of antenna 12. In otherwords, it is possible to suppress the deterioration of the radarperformances caused by the multiple reflections.

Modifications of Embodiment 1

The position of installation of antenna 12 may be varied depending onthe shape of reflector 22.

FIG. 5A is a drawing illustrating a position of installation of antenna12 in light apparatus U1 according to Modification 1. FIG. 5B is adrawing illustrating a position of installation of antenna 12 in lightapparatus U1 according to Modification 2. In FIGS. 5A and 5B, only lampunit 20 a among lamp units 20 a, 20 b, and 20 c is illustrated.

Light apparatus U1 according to the Modification 1 and light apparatusU1 of Modification 2 has a mode configured such that radar unit 10 setsthe direction of transmission and reception of the electromagnetic wavesin the same direction as the direction in which lamp unit 20 airradiates light.

In this mode, when quadrangular pyramidal reflector 22 a described inthe above-described embodiment is used, the array direction of antenna12 and the extending direction of front end portion 22 aa of reflector22 a become parallel to each other, and many of the multiple reflectedcomponents of the reflected wave come to antenna 12.

From this point of view, in both light apparatus U1 of the Modification1 and light apparatus U1 of Modification 2, front end portion 22 aa ofreflector 22 a is formed in to a shape having a protrusion in the +Xdirection so that the extending direction of front end portion 22 aa ofreflector 22 a is in a non-parallel state with the array direction ofthe antenna 12.

Specifically, reflector 22 a according to Modification 1, wherein frontend portion 22 aa of the reflector 22 a has a triangular shape having anapex in the +X direction in plan view, and the array direction of theantenna 12 is set to have an angle of 9 degrees or more (θ in FIG. 5A)with respect to the extending direction of front end portion 22 aa ofreflector 22 a in plan view.

Further, front end portion 22 aa of reflector 22 a of the Modification 2has an arcuate shape protruding in the direction of the +X direction inplan view.

Therefore, in any of light apparatus U1 according to the Modification 1and light apparatus U1 according to the Modification 2, the reflectedwaves arriving at front end portion 22 aa of reflector 22 a can bereflected in +Y direction or −Y direction in the same manner as lightapparatus U1 according to Embodiment 1.

The same effect can also be expected when front end portion 22 aa ofreflector 22 a has a concave shape with respect to +X direction in planview. For example, the concave shape may be an arc shape or a saw shape,and the end portion may have a meander line shape or have a slit.

Embodiment 2

Next, with reference to FIGS. 6 to 9, a description will be given of aconfiguration of light apparatus U1 according to Embodiment 2. Lightapparatus U1 according to Embodiment 2 differs from Embodiment 1 inhaving garnish material 40. Note that description of the structure incommon with Embodiment 1 is omitted.

FIG. 6 is a general drawing illustrating an example of a configurationof light apparatus U1 according to Embodiment 2. FIG. 7 is a sectionalside view illustrating an example of a configuration of light apparatusU1 according to Embodiment 2. FIG. 8 is a perspective view illustratingan example of a configuration of garnish material 40 according toEmbodiment 2. FIG. 9 is a plan view of radar unit 10 according toEmbodiment 2 viewed from above.

Garnish material 40 is a design member, and is disposed to configure apart of the exterior of the vehicle by surrounding the region wherelight emitted from light source 21 passes through at the front side oflamp unit 20 and radar unit 10. Garnish material 40 is formed as asubstantially rectangular frame member surrounding the outer peripheryof front cover 30 a, for example, on the front face of the vehicle body(see FIG. 8). The shape of garnish material 40 in FIG. 6 may be a shapethat surrounds the entire periphery of front cover 30 a, and the garnishmaterial may be a shape that surrounds partially the periphery of frontcover 30 a.

Garnish material 40 has lens 40 a for condensing or diffusing(condensing in this case) the electromagnetic wave in an area throughwhich the electromagnetic waves transmitted and received by antenna 12passes (that is, a front area of antenna 12). Lens 40 a typicallynarrows a beam of the electromagnetic wave transmitted by antenna 12,and transmits the same forward, and condenses the reflected wave, whichis the electromagnetic wave reflected by and returned from the target,on antenna 12.

As the material of garnish material 40, for example, a resin materialsuch as ABS resin or polypropylene resin is used. Garnish material 40 isformed by, for example, resin molding (for example, injection molding),and lens 40 a is formed as part of the shape of garnish material 40.Garnish material 40, for example, is different from front cover 30 a andis formed of an opaque material.

Lens 40 a is formed of a semi-cylindrical or parabolic cylindrical lens,which, for example, protrudes in +X direction and extends in the ±Ydirection. Lens 40 a of the semi-cylindrical or parabolic cylindricalshape has substantially the same shape in side cross section at anyposition in ±Y direction, so that a refractive angle of the reflectedwave reaching the different positions in the ±Y direction can be made tobe the same. As a result, the reflected waves coming from the outside ofthe apparatus are prevented from entering the antenna 12 from thevarious directions (for example, +Y direction side −Y direction sidewith respect to the antenna 12). In other words, it is possible toprevent deterioration in the accuracy of detection of an object (forexample, deterioration in accuracy due to mutual interference ordeterioration in accuracy due to a change in phase difference).

As described above, according to in-vehicle light apparatus U1 ofEmbodiment 2, garnish material 40 can function as a cover member forprotecting radar unit 10, and a dielectric lens for condensingelectromagnetic waves transmitted and received by radar unit 10.

This makes it possible to save space for installation of the in-vehiclelight apparatus U1 in a vehicle body while improving the radarperformance in radar unit 10, while maintaining the exterior design ofthe vehicle. This also makes it possible to prevent the deterioration ofthe radar performance caused by the multiple reflections generatedbetween radar unit 10 and the other components arranged in front ofradar unit 10, since radar unit 10 can transmit and receive theelectromagnetic waves without any other members (for example, a bumper)other than garnish material 40.

(Modified Modes)

Embodiments of the present invention are not limited to theabove-described Embodiments 1 and 2, and various modified modes areconceivable.

In Embodiments 1 and 2, although a headlight is illustrated as anexample of a target to be applied to light apparatus U1, light apparatusU1 according to the present disclosure can also be applied to a taillight or a small light.

Further, in Embodiments 1 and 2, antenna 12 of radar unit 10 is disposedin front of reflector 20 as an example of a suitable positionalrelationship between antenna 12 and reflector 20. However, theembodiments of the present invention are not limited to these modes, andantenna 12 of radar unit 10 may be disposed at a rear position relativeto a distal end portion of reflector 20 in plan view. In this case aswell, the effect of suppressing the occurrence of multiple waves byarranging the distal end portion of reflector 20 and the antenna arraydirection of radar unit 10 in a non-parallel relationship can beexpected.

Further, in Embodiments 1 and 2, as an example of light apparatus U1, amode of a horizontal type radar unit 10 using an end-fire array antennais illustrated. However, light apparatus U1 according to the presentdisclosure can be applied not only to horizontal type radar unit 10, butalso to a vertical type radar unit (that is, a radar unit having a shortlength in the ±X direction) using a patch antenna or the like having adirectional characteristics in the normal direction of the boardsurface.

In Embodiments 1 and 2, an end fire array antenna is illustrated as anexample of an antenna element constituting antenna 12. However, antenna12 may be constituted by a conductor pattern formed on circuit board 11,and it may be constituted by a Yagi array antenna, a Fermi antenna, apost-wall waveguide antenna, a post-wall horn antenna, or the like, inaddition to the end fire array antenna.

Further, in Embodiments 1 and 2, a semi-cylindrical lens is illustratedas an example of the shape of lens 40 a of garnish material 40. However,the shape of lens 40 a may be a dome-shaped lens, a double-sided convexlens, a ball lens, a Fresnel lens, a combination thereof, or acombination of concave lens and these lenses. Further, as lens 40 a,there may be applied a concave lens that diffuses the electromagneticwaves transmitted from antenna 12.

Further, in Embodiments 1 and 2, as an example of light apparatus U1, amode having three lamp units 20 is illustrated. However, light apparatusU1 according to the embodiment of the present invention may have onlyone lamp unit 20.

According to an in-vehicle light apparatus according to an example ofthe present disclosure, it is possible to suppress deterioration ofradar performance caused by multiple reflections with an integratedradar and lamp configuration.

Embodiment 3

In the conventional in-vehicle light apparatus, the radar apparatus andthe light source of the lamp are disposed close to each other.Therefore, in the in-vehicle light apparatus according to the prior art,there has been a problem that an electronic component such as amicrocomputer of a radar apparatus is damaged by radiant heat from thelight source, and the operation of the radar apparatus becomes unstable.

In the in-vehicle light apparatus according to the prior art, theelectromagnetic wave transmitted from the radar apparatus and returnedby being reflected by the target may be re-reflected by the reflector ofthe lamp (the reflective member which condenses light emitted from thelight source and controls the irradiation range of the light) and reachthe antenna of the radar apparatus. In particular, since the reflectoris a reflective member having a planar spread, it is possible to causemultiple reflections with respect to the circuit board and the likewhere the antenna is disposed, and to generate a standing wave betweenthe reflector and the antenna. Then, the standing wave is superimposedon the electromagnetic wave that directly arrives at the antenna fromthe target, and a blind spot area in which the target cannot be detectedis generated in the reception characteristics of the antenna.

An example of the present disclosure provides an in-vehicle lightapparatus capable of suppressing the propagation of radiant heat and thepropagation of electromagnetic waves to a radar apparatus side from thelamp side while the radar apparatus and the lamp are integrallyconstituted.

In each drawing, in order to clarify the positional relationship in eachconfiguration, a common orthogonal coordinate system (X, Y, Z) isillustrated with reference to a forward direction in which the radarapparatus (corresponding to a radar unit of the present disclosure)transmits the electromagnetic wave to the outside the apparatus (thatis, the direction of detection of an object). In the followingdescription, a plus direction of the X-axis represents the forward inwhich the radar apparatus transmits an electromagnetic wave to theoutside the apparatus (hereinafter referred to as “forward” or “firstdirection”), a plus direction of the Y-axis represents the left sidedirection of the radar apparatus (hereinafter abbreviated as “leftdirection”) and a plus direction of the Z-axis represents upward ofradar apparatus (hereinafter abbreviated as “upward”).

In the following description, +Z direction corresponds to the upward ofthe vehicle, and a direction about 30 degrees in the +Y direction from+X direction corresponds to the direction of travel of the vehicle.

Hereinafter, an example of the configuration of the in-vehicle lightapparatus according to Embodiment 3 (hereinafter abbreviated as “lightapparatus”) will be described. The light apparatus according toEmbodiment 3 is applied to a headlight configured to illuminate thefront of the vehicle. Note that only the configuration of a headlight onthe right front of the vehicle will be described.

FIG. 10A is a perspective view illustrating a state of installation inthe vehicle of light apparatus U2 according to Embodiment 3. FIG. 10B isa plan view illustrating a state of installation in the vehicle of lightapparatus U2 according to Embodiment 3. FIG. 10C is a front viewillustrating a state of installation in the vehicle of light apparatusU2 according to Embodiment 3.

Light apparatus U2 according to Embodiment 3 includes radar unit 110,lamp units 120 a, 120 b, and 120 c.

In light apparatus U2 according to Embodiment 3, three lamp units 120 a,120 b, and 120 c are arranged adjacent along the left-right direction,and radar unit 110 is disposed on a lower side of lamp units 120 a, 120b, and 120 c.

Radar unit 110 according to Embodiment 3 transmits an electromagneticwave obliquely rightward (+X direction) with respect to the direction oftravel of the vehicle, and performs detection of an object present inthe corresponding direction. Then, a radar unit (not illustrated) builtin the left headlight performs detection of an object present obliquelyleftward with respect to the direction of travel of the vehicle.

FIG. 11 is a sectional side view illustrating an example of aconfiguration of light apparatus U2 according to Embodiment 3. FIG. 12is a plan view of radar unit 110 according to Embodiment 3 viewed fromabove. FIG. 13 is a plan view illustrating a positional relationshipbetween radar unit 110 and lamp units 120 a, 120 b, and 120 c of lightapparatus U2 according to Embodiment 3. FIG. 14 is an upper perspectiveview illustrating the positional relationship between radar unit 110 andlamp units 120 a, 120 b, and 120 c of light apparatus U2 according toEmbodiment 3. In FIG. 13 and FIG. 14, illustration of separator 114 isomitted.

Lamp unit 120 a includes light source 121 a and reflector 122 a. Lampunit 120 a is housed in lamp housing 130 together with lamp units 120 band 120 c.

Lamp housing 130 forms a storage space in the front end region of thevehicle, and lamp units 120 a, 120 b, and 120 c in the storage space.Lamp housing 130 also has front cover 130 a configured to cover thefront face of the storage space. Lamp housing 130 is made of, forexample, a resin material (for example, polycarbonate and the like).Front cover 130 a is made of, for example, a resin material havingtransparency to light (for example, polycarbonate and the like).

Light source 121 a is, for example, an incandescent lamp, and emitslight toward the front (in this case, a direction about 30 degrees tothe −Y side from +X direction). Light source 121 a is attached to a rearside wall of lamp housing 130. Note that a light source having acondensing lens may be used as light source 121 a.

Reflector 122 a is disposed so as to surround the periphery of lightsource 121 a, collects light emitted from light source 121 a, andadjusts an irradiation range of light. Reflector 122 a is formed of, forexample, a quadrangular pyramid-shaped cylindrical member having anopening directed toward the front side and increasing in openingdiameter toward the front side. Reflector 122 a is formed of a metalmember such as an aluminum material, for example. Reflector 122 a may beformed by metallizing a resin member.

Lamp units 120 b and 120 c have the same configuration as lamp unit 120a, and are made up of light sources 121 b and 121 c and reflectors 122 band 122 c surrounding light sources 121 b and 121 c, respectively. Lampunits 120 a, 120 b, and 120 c are equipped with a system thatautomatically shifts the headlight irradiation area, for example, calledan adaptive high beam system.

Hereinafter, any one of lamp unit 120 a, lamp unit 120 b, and lamp unit120 c is abbreviated as “lamp unit 120”, “light source 121”, and“reflector 122” unless particularly distinguished.

Radar unit 110 includes circuit board 111, antenna 112, signalprocessing IC 113, separator 114, and dielectric lens 115.

Circuit board 111 is a board on which antenna 112 and signal processingIC 113 are mounted. As circuit board 111, for example, a Printed CircuitBoard (PCB), a semiconductor substrate with built-in signal processingIC 113, or the like is used.

From the viewpoint of miniaturization of light apparatus U2, circuitboard 111 is disposed on the lower side of reflector 122 so that theboard surface extends substantially along the horizontal direction.Here, “substantially along the horizontal direction” includes not only astate in which the board surface is completely horizontal to the groundbut also a state in which the board surface is inclined with respect tothe ground. Circuit board 111 may be disposed on the upper side ofreflector 122.

In other words, radar unit 110 constitutes a horizontal type millimeterwave radar in which circuit board 111 is disposed horizontally. As aresult, radar unit 110 is thinner than lamp unit 120 in the ±Zdirections.

Antenna 112 is disposed in the front area of the board surface ofcircuit board 111 and transmits electromagnetic wave Ft forward (+Xdirection), and receives reflected wave Fr which is the electromagneticwave reflected by a target.

Antenna 112 is, for example, an end-fire array antenna havingdirectional characteristics in the direction of the front end side ofcircuit board 111. The end-fire array antenna is configured to include aplurality of strip conductors which are arranged such that thelongitudinal direction thereof are in parallel, and transmits andreceives electromagnetic waves along the direction in which theplurality of strip conductors are arranged. Antenna 112 is composed of,for example, six end-fire array antennas (hereinafter also referred toas “antenna elements”) arranged adjacent along ±Y direction. Antenna 112is formed as a phased array antenna by six antenna elements.

Antenna 112 is disposed on the front side (that is, on the outside sideof the vehicle) relative to reflector 122. In other words, antenna 112is arranged so as not to overlap with reflector 122 in plan view. Thisprevents antenna 112 and reflector 122 from facing each other, therebypreventing the generation of the standing wave between antenna 112 andreflector 122.

A plurality of the antenna elements constituting antenna 112 arearranged such that the array directions of the plurality of the antennaelements is non-parallel to the extending direction of front endportions 122 aa, 122 ba, and 122 ca of reflector 122 in plan view (seeFIGS. 13 and 14). More preferably, the array direction of antenna 112 isset to have an angle ranging from 9 degrees to 171 degrees (angle θ inFIG. 13) with respect to the extending direction of front end portions122 aa, 122 ba, and 122 ca of reflector 122 in plan view. This makes thereflected waves arriving at front end portions 122 aa, 122 ba, and 122ca of reflector 122 are diffused away from a position of installation ofantenna 112 (in +Y direction or −Y direction here) when re-reflecting atfront end portions 122 aa, 122 ba and 122 ca of reflector 122. In otherwords, it is possible to suppress the amount of the multiple reflectedcomponents of the reflected waves arriving at antenna 112.

For example, signal processing IC 113 sends a high-frequency drivesignal to antenna 112 to transmit an electromagnetic wave Ft (forexample, an electromagnetic wave in the millimeter wave band) fromantenna 112, or performs reception processing for a received signalrelating to a reflected wave received by antenna 112. Then, receptionprocessing (for example, detection wave processing or frequency analysisprocessing) by signal processing IC 113 is performed to detect thedistance to the target (for example, a vehicle or a person), the azimuthwhere the target is present, and other parameters such as the reflectionintensity and speed of the target. Here, since the reception processingby signal processing IC 113 is the same as that of a knownconfiguration, detailed description thereof is omitted here.

Separator 114 is disposed to partition the space between lamp unit 120and radar unit 110 to shield the transmission of radiant heat andelectromagnetic waves between lamp unit 120 and radar unit 110.Separator 114 according to Embodiment 3 is disposed so as to surroundthe periphery of circuit board 111, and also functions as a radarhousing (hereinafter also referred to as radar housing 114) foraccommodating circuit board 111. Separator 114 is mounted on the lowersurface of lamp housing 130 by using a fixing member (for example, ascrew) in a state in which circuit board 111 is housed.

In particular, separator 114 suppresses the radiant heat emitted fromlight source 121 from propagating to circuit board 111 (for example,signal processing IC 113) and suppresses the propagation of theelectromagnetic waves coming from the front and reflected by reflector122 to antenna 112. The radiant heat transmitted to separator 114, forexample, diffuses to the whole of separator 114, and is dissipated tothe member and the outer space that come into contact with separator114. Accordingly, radiant heat emitted from light source 121 suppressesoverheating of signal processing IC 113 mounted on circuit board 111.

Further, separator 114 suppresses the propagation of reflected wavesreflected by the target to antenna 112 when re-reflected by reflector122. Separator 114 also functions to shield the side lobe component ofthe electromagnetic wave emitted from antenna 112 from being directedtoward light source 121 (for example, the control circuit (notillustrated) that controls light source 121).

Any material may be used for separator 114 as long as it is a membercapable of shielding the transmission of radiant heat andelectromagnetic waves, but typically, a metal member (for example,aluminum or copper) is used. In view of facilitating thermal diffusion,the material of separator 114 is preferably a material having a higherthermal conductivity than the material of lamp housing 130 (for example,a resin material), and a metal member such as aluminum is morepreferable. On the other hand, separator 114 may be constituted by acombination of a material having a high thermal conductivity (forexample, a carbon containing member) and a member capable of shieldingthe transmission of electromagnetic waves.

Dielectric lens 115 is mounted on the window portion formed on the frontface of radar housing 114 (separator 114), narrows the beam ofelectromagnetic wave Ft transmitted by antenna 112, transmits the sameforward, and condenses the reflected wave returned from the target toantenna 112.

Dielectric lens 115 is, for example, formed of a semi-cylindrical orparabolic cylindrical lens, which protrudes in +X direction and extendsin the ±Y direction. Dielectric lens 115 of the semi-cylindrical shapeor the parabolic cylinder shape has substantially the same shape incross section at any position in ±Y direction, so that a refractiveangle of the reflected wave reaching the different positions in the ±Ydirection can preferably be made to be the same. As a result, thereflected waves coming from the outside of the apparatus are preventedfrom entering antenna 112 from the various directions (for example, +Ydirection side −Y direction side with respect to antenna 112). In otherwords, it is possible to prevent deterioration in the accuracy ofdetection of an object (for example, deterioration in accuracy due tomutual interference or deterioration in accuracy due to a change inphase difference).

Advantageous Effect of One Example

As described above, in-vehicle light apparatus U2 of Embodiment 3includes: lamp unit 120 including light source 121 configured to emitlight in a first direction, (forward in this case) and reflector 122surrounding light source 121; radar unit 110 having circuit board 111disposed such that the board surface extends in a horizontally manner ona lower side or an upper side of lamp unit 120, and antenna 112 disposedon the first direction side relative to reflector 122 in the boardsurface of circuit board 111 to transmit electromagnetic waves in thefirst direction and to receive the reflected waves thereof; andseparator 114 is disposed so as to partition a space between lamp unit120 and radar unit 110 to shield the transmission of radiant heat andelectromagnetic waves between lamp unit 120 and radar unit 110.

Therefore, according to in-vehicle light apparatus U2 of Embodiment 3,transmission of the radiant heat from light source 121 of lamp unit 120to radar unit 110 by separator 114 may be suppressed. Accordingly, theoccurrence of the operation failure of radar unit 110 due to theinfluence of heat may be suppressed.

According to in-vehicle light apparatus U2 of Embodiment 3, the spreadof the electromagnetic wave (multiple reflected components of thereflected wave) re-reflected by reflector 122 by separator 114 out ofthe reflected wave from the target to antenna 112 may be suppressed.This makes it possible to suppress the situation in which the multiplereflected components of the reflected waves are superimposed on thereflected waves coming directly from the target to antenna 112, therebydeteriorating the reception characteristics of antenna 112.

Embodiment 4

Next, with reference to FIG. 15, a description will be given of aconfiguration of light apparatus U2 according to Embodiment 4. Lightapparatus U2 according to Embodiment 4 differs from Embodiment 3 in aconfiguration of separator 114. Note that description of the structurein common with Embodiment 3 is omitted. (hereinafter, the same appliesto the other embodiments).

FIG. 15 is a sectional side view illustrating an example of aconfiguration of light apparatus U2 according to Embodiment 4.

Separator 114 according to Embodiment 4 has first extending portion 114a extending to the front side relative to circuit board 111, and has aconfiguration of contacting dielectric lens 115 (that is, the covermember) and front cover 130 a at first extending portion 114 a. Morespecifically, first extending portion 114 a extends to a position cominginto contact with the front end face of dielectric lens 115 and thefront end face of front cover 130 a.

Separator 114 according to Embodiment 4 absorbs radiant heat emittedfrom light source 121, and the heat is transferred to the front end faceof dielectric lens 115 and the front end face of front cover 130 athrough first extending portion 114 a and the front end face of frontcover 130 a to raise the temperature of the front end face of dielectriclens 115 and of the front end face of front cover 130 a. In other words,in Embodiment 4, the heat of separator 114 is utilized for defrosting,defogging or preventing snow accretion of the front end face ofdielectric lens 115 and the front end face of front cover 130 a.

Here, although first extending portion 114 a of separator 114 is incontact with both the front end surface of dielectric lens 115 and thefront end face of front cover 130 a, it may be configured to come intocontact with at least the front end surface of dielectric lens 115. Onthe other hand, first extending portion 114 a is preferable even ifother cover members are used instead of dielectric lens in the front ofantenna 112.

As described above, according to light apparatus U2 of Embodiment 4, itis possible to raise the temperature of dielectric lens 115 exposedoutside the vehicle by using the radiant heat emitted by light source121. This may suppress attachment of dielectric lens 115 to be preventedfrom adhering to the ice, snow or the like. This makes it possible toimprove the output gain and the reception gain in antenna 112.

Embodiment 5

Next, with reference to FIG. 16, a description will be given of lightapparatus U2 according to Embodiment 5. Light apparatus U2 according toEmbodiment 5 differs from Embodiment 3 in a configuration of separator114.

FIG. 16 is a sectional side view illustrating an example of aconfiguration of light apparatus U2 according to Embodiment 5.

Separator 114 according to Embodiment 5 has second extending portion 114b extending from a region above circuit board 111 to the rear side ofcircuit board 111. Further, second extending portion 114 b has astructure extending toward the lower side with respect to the horizontaldirection. With such a configuration, second extending portion 114 bre-reflects the components of the reflected wave from the targetdirected rearward of circuit board 111 so as to be warped downward tosuppress the reflected wave from proceeding from the back side towardantenna 112 again. This makes it possible to suppress the detection ofthe reflected wave from the rear of circuit board 111 in antenna 112.

In the case where circuit board 111 is disposed above reflector 122,second extending portion 114 b has a structure extending toward theupper side with respect to the horizontal direction.

As described above, according to light apparatus U2 of Embodiment 5, theelectromagnetic waves reaching antenna 112 due to multiple reflectionsmay be suppressed to improve the reception characteristics in antenna112.

Embodiment 6

Next, light apparatus U2 according to Embodiment 6 will be describedwith reference to FIG. 17. Light apparatus U2 according to Embodiment 6differs from Embodiment 3 in terms of the structure of Separator 14.

FIG. 17 is a sectional side view illustrating an example of theconfiguration of light apparatus U2 according to Embodiment 6.

Separator 114 according to Embodiment 6 has third extending portion 114c extending away from antenna 112 as it goes forward on the front sideof circuit board 111. Third extending portion 114 c has a shape inclinedupward as it goes forward. That is, the shape of separator 114 accordingto Embodiment 6 is set so that the opening diameter of the windowportion for transmitting and receiving an electromagnetic wave isincreased as it goes toward the front side of antenna 112.

This makes it possible to suppress a decrease in the output gain ofantenna 112 due to reflection of components of an electromagnetic wavetransmitted from antenna 112 spreading in the radial direction byseparator 114 when antenna 112 transmits the electromagnetic wave, whilereducing the size of separator 114 (that is, the radar housing).

As described above, according to light apparatus U2 of Embodiment 6, adecrease in the output gain of antenna 112 caused by the reflection ofthe electromagnetic wave in separator 114 can be suppressed whilereducing the size of the entire apparatus.

Embodiment 7

Next, a light apparatus U2 according to Embodiment 7 will be describedwith reference to FIG. 18. Light apparatus U2 according to Embodiment 7differs from Embodiment 3 in that separator 114 has electromagnetic waveabsorbing material 114 d.

FIG. 18 is a sectional side view illustrating an example of aconfiguration of light apparatus U2 according to Embodiment 7.

Separator 114 according to Embodiment 7 has an electromagnetic waveabsorbing material 114 d arranged between circuit board 111 and theinner wall surface of radar housing 114. Electromagnetic wave absorbingmaterial 114 d absorbs the components which are directed toward the rearside of antenna 112 of the reflected wave from the target, andsuppresses the occurrence of multiple reflections of the reflected wavebetween separator 114 and circuit board 111.

Examples of the material of the electromagnetic wave absorbing material114 d include a conductive absorbing material configured to absorb acurrent generated by the electromagnetic wave due to a resistance lossin the interior of the material, a dielectric wave absorbing material(for example, carbon) configured to use a dielectric loss caused by apolarizing response of molecules, a magnetic wave absorbing material(for example, iron, nickel, ferrite) and the like configured to absorb aradio wave due to a magnetic loss of the magnetic material.

Further, examples of the material of the electromagnetic wave absorbingmaterial 114 d may also include a material having high heatconductivity, for example, a graphite sheet or the like may be used.

As described above, according to light apparatus U2 of Embodiment 7, theelectromagnetic waves reaching antenna 112 due to multiple reflectionsmay be suppressed to improve the reception characteristics in antenna112.

(Modified Modes)

Embodiments of the present invention are not limited to theabove-described Embodiments 3 to 7, but various modified modes are alsoconceivable.

In Embodiments 3 to 7, various modes of an example of the configurationof light apparatus U2 are illustrated. However, it is needless to saythat a combination of modes described in the respective embodiments mayalso be used.

Further, in the above third to Embodiments 3 to 7, the headlight isillustrated as an example of the target to be applied of light apparatusU2, but light apparatus U2 according to the present disclosure can beapplied to a tail light or a small light.

Further, in Embodiments 3 to 7, as an example of light apparatus U2, amode of horizontal type radar unit 110 using an end-fire array antennais illustrated. However, light apparatus U2 according to the presentdisclosure can be applied not only to horizontal type radar unit 110 butalso to a vertical type radar unit using a patch antenna or the likehaving directional characteristics in the normal direction of the boardsurface.

Further, in Embodiments 3 to 7 described above, as an example of theposition of installation of circuit board 111, a case of the lower sideof reflector 122 is illustrated. However, as the position ofinstallation of circuit board 111, the upper side of reflector 122 isalso applicable. Note that in this case, the position of installation ofseparator 114 is on the lower surface side of circuit board 111.

In Embodiments 3 to 7, an end-fire array antenna is illustrated as anexample of an antenna element constituting antenna 112. However, antenna112 only needs to be made up of a conductor pattern formed on circuitboard 111, and instead of the end-fire array antenna, a Yagi arrayantenna, a Fermi antenna, a post wall waveguide antenna, or a post wallhorn antenna or the like are also applicable.

In Embodiments 3 to 7, a semi-cylindrical lens is illustrated as anexample of the shape of dielectric lens 115. However, examples of theshape of dielectric lens 115 include a dome-shaped lens, a double-sidedconvex lens, a ball lens, a Fresnel lens, or a combination thereof, or aconcave lens and a combination thereof. In addition, as dielectric lens115, a concave lens that diffuses an electromagnetic wave transmittedfrom antenna 112 may be applied.

In Embodiments 3 to 7 described above, a mode in which three lamp units120 are provided as an example of light apparatus U2 is described.However, in-vehicle light apparatus U2 according to the embodiments ofthe present invention may have a configuration having only one lamp unit120.

According to the in-vehicle light apparatus of an example of the presentdisclosure, propagation of radiant heat and electromagnetic wave fromthe lamp side to the radar apparatus side can be suppressed.

The in-vehicle light apparatus according to an example of the presentdisclosure is an in-vehicle light apparatus for monitoring a region in afirst direction outside a vehicle, including: a lamp unit including alight source that emits light in the first direction, and a reflectorsurrounding the light source; a radar unit including a circuit boarddisposed such that a board surface extends substantially along thehorizontal direction on a lower side or an upper side of the lamp unitand an antenna disposed on the first direction side relative to thereflector in the board surface of circuit board to transmitelectromagnetic waves in the first direction and to receive thereflected waves thereof; and a separator disposed so as to partition aspace between the lamp unit and the radar unit to shield thetransmission of radiant heat and electromagnetic waves between the lampunit and the radar unit.

In an in-vehicle light apparatus according to an example of the presentdisclosure, the separator is made of a material having higher thermalconductivity than a lamp housing that houses the lamp unit.

In the in-vehicle light apparatus according to an example of the presentdisclosure, the separator is constituted by a metal member.

In an in-vehicle light apparatus according to an example of the presentdisclosure, the separator has a first extending portion extending to thefirst direction side relative to the circuit board, and the firstextending portion contacts with a cover member disposed to cover thearea where the electromagnetic waves pass through.

In an in-vehicle light apparatus according to an example of the presentdisclosure, the separator includes a second extending portion thatextends from the first extending portion to the rear side of the circuitboard, the rear side being opposite to the first direction, and thesecond extending portion reflects the electromagnetic waves reachingfrom the first direction side to the rear side of the circuit board tothe lower side or the upper side.

In the in-vehicle light apparatus according to an example of the presentdisclosure, the separator includes a third extending portion thatextends away from the antenna as it goes toward the first direction onthe first direction side of the circuit board.

In an in-vehicle light apparatus according to an example of the presentdisclosure, the separator includes a member having electromagnetic waveabsorption characteristics.

In the in-vehicle light apparatus according to an example of the presentdisclosure, the antenna is made up of an end-fire array antenna.

Embodiment 8

Incidentally, in the in-vehicle light apparatus of this type, the radarapparatus is disposed in a state of being covered with the cover memberin order to protect the built-in radar apparatus. The radar apparatustransmits and receives electromagnetic waves to and from the areaoutside the vehicle via the cover member.

However, depending on a driving environment of the vehicle, there arecases where ice, snow, and frost adheres to the cover member. In such acase, due to the ice, snow or the like adhering to the cover member,there is a problem that the output gain and reception gain of theelectromagnetic wave transmitted and received by the radar apparatus arelowered, and the detection accuracy of the detection of an object of theradar apparatus is lowered.

In view of such problems described above, one example of the presentdisclosure provides a control apparatus of an in-vehicle light apparatuscapable of suppressing decrease in radar performance caused by ice, snowor the like adhering to the cover member disposed in front of the radarapparatus.

[Configuration of In-Vehicle Light Aparatus]

Hereinafter, an example of the configuration of an in-vehicle lightapparatus (hereinafter abbreviated as “light apparatus”) according toEmbodiment 8 will be described. The light apparatus according toEmbodiment 1 is applied to a headlight configured to illuminate thefront of the vehicle. Note that only the configuration of a headlight onthe right front of the vehicle will be described.

In each drawing, in order to clarify the positional relationship of eachcomponent, a common orthogonal coordinate system based on the forwarddirection (that is, the direction subject to detection of an object) inwhich radar apparatus transmits an electromagnetic wave to the outsideapparatus (X, Y, Z). In the following description, the plus direction onthe X-axis represents the front direction (hereinafter abbreviated as“forward direction” or “first direction”) in which the radar apparatustransmits an electromagnetic wave to the outside the apparatus, and theplus direction on the Y-axis represents the right direction of a side ofthe radar apparatus (hereinafter abbreviated as “rightward direction”),and the plus direction of the Z-axis represents the upward of the radarapparatus (hereinafter abbreviated as “upward direction”).

In the following description, +Z direction is corresponds to the upwarddirection of the vehicle, and the direction about 30 degrees to theminus Y direction from the +x direction corresponds to the direction oftravel of the vehicle.

FIG. 19 is a perspective view illustrating a state of installation inthe vehicle of light apparatus U3 according to Embodiment 8.

Light apparatus U3 according to Embodiment 8 includes radar apparatus210, lamps 220 a, 220 b, and 220 c, and Electronic Control Unit (ECU)200 (see FIG. 20).

In light apparatus U3 according to Embodiment 8, three lamps 220 a, 220b, and 220 c are arranged adjacent to each other along the left-rightdirection, and radar apparatus 210 is disposed on the lower side oflamps 220 a, 220 b, and 220 c.

Radar apparatus 210 according to Embodiment 8 transmits anelectromagnetic wave in an obliquely right direction (+X direction) withrespect to the direction of travel of the vehicle, and performsdetection of an object present in that direction. Then, a radarapparatus (not illustrated) built in the left headlight performsdetection of an object present in the obliquely leftward direction withrespect to the direction of travel of the vehicle.

FIG. 20 is a sectional side view illustrating an example of theconfiguration of the light apparatus U3 according to this embodiment.FIG. 21 is a plan view of radar apparatus 210 according to Embodiment 8as seen from above.

Lamp 220 a includes light source 221 a and reflector 222 a. Lamp 220 ais stored in lamp housing 230 together with lamps 220 b and 220 c.

Lamp housing 230 forms a storage space in the front end region of thevehicle, and houses radar apparatus 210 and lamps 220 a, 220 b, and 220c in the storage space. Lamp housing 230 has front cover 230 a thatcovers the front face of the storage space. Lamp housing 230 is made of,for example, a resin material (for example, polycarbonate and the like).Further, front cover 230 a is formed of, for example, a resin material(for example, polycarbonate and the like) having light permeability.

Light source 221 a is, for example, an incandescent bulb, and emitslight toward the front (here, the direction about 30 degrees from +Xdirection toward the −Y side). Light source 221 a is attached to therear side wall of lamp housing 230. A light source having a condensinglens may be used as light source 221 a.

Reflector 222 a is disposed so as to surround the periphery of lightsource 221 a to collect light emitted from light source 221 a and adjustthe irradiation range of light. Reflector 222 a is formed of, forexample, a quadrangular pyramid-shaped cylindrical member whose openingdirected to the front side and increasing in diameter as it goes towardthe front. Reflector 222 a is formed of a metal member such as analuminum material, for example. Further, reflector 222 a may be formedby metallizing a resin member.

Lamps 220 b and 220 c have the same configuration as lamp 220 a, and areeach made up of the light source and a reflector surrounding the lightsource. Lamps 220 a, 220 b, and 220 c are equipped with a system thatautomatically shifts the irradiation area of the headlight, for example,referred to as an adaptive high beam system.

In the following description, any one of lamp 220 a, lamp 220 b, andlamp 220 c is abbreviated as “lamp 220”, “light source 221”, and“reflector 222” unless otherwise specifically distinguished.

Radar apparatus 210 includes circuit board 211, antenna 212, signalprocessing IC 213, and separator 214.

In addition, radar apparatus 210 according to Embodiment 8 transmits andreceives an electromagnetic wave to and from the front regions outside avehicle via dielectric lens 215. In other words, dielectric lens 215according to Embodiment 8 also functions as a cover member that protectsradar apparatus 210 (hereinafter also referred to as “cover member215”).

Circuit board 211 is a board on which antenna 212 and signal processingIC 213 are mounted. As circuit board 211, for example, a Printed CircuitBoard (PCB), a semiconductor substrate with built-in signal processingIC 213, or the like is used.

In view of miniaturization of light apparatus U3, circuit board 211 isdisposed on the lower side of reflector 222 such that the board surfaceextends along the horizontal direction. Circuit board 211 may bedisposed on the upper side of reflector 222.

Antenna 212 is disposed in the front area of the board surface ofcircuit board 211 and transmits electromagnetic wave Ft forward (+Xdirection), and receives reflected wave Fr which is the electromagneticwave reflected by a target.

Antenna 212 comprises, for example, an end-fire array antenna havingdirectional characteristics in the direction of the front end side ofcircuit board 211. The end-fire array antenna is configured to include aplurality of strip conductors which are arranged such that thelongitudinal direction thereof are in parallel, and transmits andreceives electromagnetic waves along the direction in which theplurality of strip conductors are arranged. Antenna 212 is composed of,for example, six end-fire array antennas (hereinafter also referred toas “antenna elements”) arranged adjacent to each other along ±Ydirection. Antenna 212 is formed as a phased array antenna by sixantenna elements.

Antenna 212 is disposed on the front side of reflector 222. In otherwords, antenna 212 is disposed so as not to overlap with reflector 222in plan view. This prevents antenna 212 and reflector 222 from facingeach other, thereby preventing the generation of the standing wavebetween antenna 212 and reflector 222.

For example, signal processing IC 213 transmits a high-frequency drivesignal to antenna 212 to transmit an electromagnetic wave (for example,an electromagnetic wave in the millimeter wave band) from antenna 212,or performs reception processing for a received signal relating to areflected wave received by antenna 212. Then, detection of the distanceto the target (for example, a vehicle or a person), the azimuth wherethe target is present, and the reflection intensity and speed of thetarget and the like is performed by reception processing (for example,detection wave processing or frequency analysis processing) by signalprocessing IC 213. Here, since the reception processing by signalprocessing IC 213 is the same as a known configuration, detaileddescription thereof is omitted here.

Separator 214 is disposed so as to partition a space between lamp 220and radar apparatus 210, and shields the transmission of radiant heatbetween lamps 220 a, 220 b, and 220 c and radar apparatus 210.Specifically, separator 214 suppresses propagation of radiant heatemitted from light source 221 to circuit board 11 (for example, signalprocessing IC 213). Accordingly, radiant heat emitted from light source221 suppresses overheating of signal processing IC 213 mounted oncircuit board 211. Separator 214 also functions to suppress propagationof an electromagnetic wave that arrives from the front and is reflectedby reflector 222 to antenna 212.

Note that separator 214 according to Embodiment 8 is disposed so as tosurround circuit board 211, and also functions as a radar housing thathouses circuit board 211. Separator 214 is mounted on the lower surfaceof lamp housing 230 by using a fixing member (for example, a screw) in astate in which circuit board 211 is stored.

Further, separator 214 extends to the front side relative to circuitboard 211 and has an extending portion 214 a that contacts dielectriclens 215. In other words, separator 214 functions to absorb the radiantheat emitted from light source 221 and transfers the heat to the frontend face of dielectric lens 215 to increase the temperature of the frontend face of dielectric lens 215 (Heat in FIG. 20 represents the heatthat separator 214 may transfer). In FIG. 20, although extending portion214 a of separator 214 is in contact with both the front end surface ofdielectric lens 215 and the front end face of front cover 230 a, it maybe configured to come into contact with at least the front end face ofdielectric lens 215.

The material of separator 214 is preferably a material having higherthermal conductivity than the material of lamp housing 230 (for example,a resin material), and typically, a metal member (for example, aluminumor copper) or a carbon material is used.

Dielectric lens 215 (corresponding to “cover member” of the presentdisclosure) is mounted on the window portion formed on the front face ofseparator 214, narrows the beam of electromagnetic wave Ft transmittedby antenna 212, transmits the same forward, and condenses the reflectedwave returned from the target to antenna 212.

Dielectric lens 215 is, for example, formed of a semi-cylindrical orparabolic cylindrical lens, which protrudes in +X direction and extendsalong the ±Y direction.

Dielectric lens 215 of the semi-cylindrical shape or the paraboliccylinder shape has substantially the same shape in side cross section atany position in ±Y direction, so that a refractive angle of thereflected wave reaching the different positions in the ±Y direction canpreferably be made to be the same. As a result, the reflected wavescoming from the outside of the apparatus are prevented from enteringantenna 212 from the various directions (for example, +Y direction side−Y direction side with respect to antenna 212). In other words, it ispossible to prevent deterioration in the accuracy of detection of anobject (for example, deterioration in accuracy due to mutualinterference or deterioration in accuracy due to a change in phasedifference).

In this embodiment, although dielectric lens 215 also functions as acover member for protecting antenna 212 or the like, a member having noelectromagnetic wave condensing function may be mounted as a covermember for protecting antenna 212 or the like.

ECU 200 (corresponding to “control apparatus” of the present disclosure)controls a driving circuit of lamp 220 to control ON/OFF of lighting oflamp 220. ECU 200 includes, for example, a Central Processing Unit(CPU), a Read Only Memory (ROM), a

Random Access Memory (RAM), an input port, an output port, and the like.ECU 200 is connected to radar apparatus 210 via an in-vehicle networkand exchanges necessary data and control signals with each other.

[Configuration of ECU]

Next, an example of configuration of ECU 200 according to Embodiment 8will be described with reference to FIG. 22 and FIG. 23.

FIG. 22 is a block diagram illustrating an example of the configurationof ECU 200 according to Embodiment 8.

ECU 200 includes reflected wave intensity acquirer 201, weatherinformation acquirer 202, and lighting controller 203.

Reflected wave intensity acquirer 201 acquires the intensity of thereflected wave detected by radar apparatus 210 from radar apparatus 210.Reflected wave intensity acquirer 201 according to Embodiment 8 uses areflected wave power as information indicating the intensity of thereflected wave. However, as information indicating the intensity of thereflected wave, other information may be used instead of the reflectedwave power.

The reflected wave power detected by radar apparatus 210 is themagnitude of the reflected wave reflected from the target present in thefront and returned to antenna 212 among the electromagnetic wavestransmitted by antenna 212 forward. The reflected wave power is detectedby signal processing IC 213 receiving processing the electromagneticwave received by antenna 212.

Weather information acquirer 202 acquires weather information at presentat the travelling position of the vehicle on which it is mounted.Weather information acquirer 202 acquires information on the travellingposition of the vehicle from a GPS receiver mounted on the vehicle, forexample. Weather information acquirer 202 acquires weather informationof the travelling position of the vehicle from a weather informationproviding apparatus (for example, a weather information providing serverprovided by a public institution).

However, the method by which weather information acquirer 202 acquiresweather information is arbitrary, and a method of identifying weatherinformation based on an image outside the vehicle reflected on thein-vehicle camera may be used, or a configuration such that the weatherinformation is set by a person on board is also applicable.

Based on the reflected wave power acquired by reflected wave intensityacquirer 201, lighting controller 203 determines the presence or absenceof adhesion of ice, snow, or frost to cover member 215 disposed in frontof radar apparatus 210, and controls ON/OFF of the lamp according to theresult of determination. Specifically, lighting controller 203 turns onlight source 221 of lamp 220 when ice, snow, frost, or the like isattached to cover member 215, uses radiant heat from light source 221 toincrease the temperature of cover member 215 via separator 214 or frontcover 230 a. Accordingly, the ice, snow, frost, or the like adhering tocover member 215 are removed from the front face of cover member 215 bymelting or evaporating.

FIG. 23 is a diagram illustrating changes in behavior of reflected wavepower when ice, snow or the like adheres to the front face of covermember 215. The dotted line graph in FIG. 23 represents a behavior ofreflected wave power when ice, snow or the like is not attached to thefront face of cover member 215, and the solid line graph represents thebehavior of reflected wave power when ice, snow or the like is attachedto the front face of cover member 215.

The horizontal axis of FIG. 23 represents time, and the vertical axisrepresents reflected wave power [W]. The peak appearing at a timing t1in FIG. 23 represents a reflected wave from the position of cover member215, and the peak appearing at a timing t2 represents a reflected wavefrom the target in front of cover member 215.

In general, when an electromagnetic wave is transmitted from antenna 212of radar apparatus 210, a part of the electromagnetic wave is reflectedby cover member 215 and returns to antenna 212. When ice, snow or thelike is adhere to the front face of cover member 215, the amount ofelectromagnetic wave reflected by cover member 215 (that is, reflectedwave power) increases due to the influence of the ice, snow or the like.When ice, snow or the like adheres to the front face of cover member215, the reflected wave power from the target outside cover member 215is lowered due to the influence of the ice, snow or the like.

Lighting controller 203 determines whether or not ice, snow or the likeis adhered to cover member 215 in consideration of the above behavior.Specifically, when the reflected wave power from the position of covermember 215 (reflected wave power detected at the timing of t1 is equalto or greater than a predetermined threshold, lighting controller 203determines that ice, snow or the like is attached to cover member 215,and turns ON lamp 220 in order to execute temperature rising processingfor cover member 215. In addition, lighting controller 203 determinesthat ice, snow or the like have been removed from cover member 215 whenthe reflected wave power from the position of cover member 215 becomesbelow a predetermined threshold during the temperature raising process,and then turns off lamp 220.

Lighting controller 203 further controls ON/OFF of lamp 220 based on theweather information acquired by the weather information acquirer 202 inorder to avoid unnecessary lighting. That is, when the deposit on covermember 215 is mud or the like, the deposit cannot be removed in manycases even when lamp 220 is turned on and the temperature of covermember 215 is increased. From this point of view, lighting controller203 turns on lamp 220 only when the weather information is snow.

Note that the above functions of ECU 200 are realized by CPU referringto a control program or various data stored in ROM or RAM, for example.

[Operation Flow of ECU]

Next, an example of the operation of ECU 200 according to thisembodiment will be described with reference to FIG. 24.

FIG. 24 is a flowchart illustrating an example of the operation of ECU200. In the flowchart illustrated in FIG. 24, for example, ECU 200 isexecuted at a predetermined interval (for example, every 10 minutes)according to a computer program.

In step S1, first, ECU 200 determines whether or not the reflected wavepower from cover member 215 is equal to or greater than the thresholdbased on the behavior of the reflected wave acquired from radarapparatus 210. At this time, if the reflected wave power from covermember 215 is equal to or greater than the threshold (Si: YES), ECU 200advances the process to step S2. On the other hand, when the reflectedwave power from cover member 215 is below threshold (Si: NO), ECU 200ends the operation flow of FIG. 24 without executing any particularprocessing.

In step S1, when an electromagnetic wave is transmitted from antenna212, ECU 200 identifies the reflected wave detected at a preset timingas a reflected wave from cover member 215, and detects the reflectedwave power (see FIG. 23).

In step S2, ECU 200 determines whether or not the weather at present issnow based on the weather information of the travelling positionacquired from the weather information providing apparatus. At this time,if the weather at present is snow (S2: YES), ECU 200 advances theprocess to step S3. On the other hand, when the weather of at present isnot snow (S2: NO), ECU 200 terminates the operation flow of FIG. 24without executing any particular processing.

In step S3, ECU 200 controls a driving circuit of lamp 220 so that lamp220 is turned on. Then, the process proceeds to step S4.

In step S4, ECU 200 determines whether or not the reflected wave powerfrom cover member 215 has decreased to a level below the threshold basedon the behavior of the reflected wave acquired from radar apparatus 210.At this time, ECU 200 waits for reflected wave power from cover member215 to fall to a value below the threshold (S4: NO), and when reflectedwave power from cover member 215 falls to a value below threshold (S4:YES), the process proceeds to step 55.

In step 55, the ECU 200 controls the driving circuit of lamp 220 so asto turn off lamp 220. Then, the operation flow illustrated in FIG. 24 isended.

In-vehicle light apparatus U3 according to Embodiment 8 performs theabove-described process, and when ice, snow or the like adheres to covermember 215 (here, dielectric lens 215), the temperature of cover member215 is increased, and ice, snow or the like is removed correspondingly.

Effect of One Example

As described above, control apparatus 200 of in-vehicle light apparatusU3 according to Embodiment 8 includes reflected wave intensity acquirer201 configured to acquire reflected wave power of an electromagneticwave transmitted forward (first direction) by radar apparatus 210, andlighting controller 203 configured to determine adhesion of ice, snow,or frost to cover member (for example, dielectric lens) 215 disposed onthe front side of radar apparatus 210 based on the reflected wave powerand control ON/OFF of lamp 220 according to the result of determination.

Accordingly, according to in-vehicle light apparatus U3 of Embodiment 8,when ice, snow, or frost is attached to cover member 215 disposed infront of radar apparatus 210, cover member 215 can be heated by theradiant heat of lamp 220 to perform snow melting or defrosting.Accordingly, it is possible to suppress a decrease in output gain and adecrease in reception gain in radar apparatus 210 due to ice, snow, orfrost adheres to cover member 215.

Further, control apparatus 200 according to this embodiment furtherincludes weather information acquirer 202 for acquiring at presentweather information at the travelling position of the vehicle on whichthe vehicle is mounted, and lighting controller 203 determines theadhesion of ice and snow to cover member 215 based on the reflected wavepower and the weather information, and controls ON/OFF of lamp 220.

Accordingly, it is possible to determine the adhesion of ice, snow, orfrost to cover member 215 disposed in front of radar apparatus 210 moreaccurately, and unnecessary lighting can be prevented.

(Modified Modes)

Embodiments of the present invention are not limited to theabove-described Embodiment 8, but various modified modes are alsoconceivable.

In the above-mentioned Embodiment 8, a mode including reflected waveintensity acquirer 201, weather information acquirer 202, and lightingcontroller 203 is illustrated as an example of ECU 200. However, ECU 200does not necessarily have to have weather information acquirer 202, andlighting controller 203 may control ON/OFF of lamp 220 only from theinformation of reflected wave power.

In the above Embodiment 8, as an example of a configuration for raisingthe temperature of dielectric lens 215 using the radiant heat emittedfrom light source 221, separator 214 that absorbs radiant heat emittedfrom light source 221 and transmits it to dielectric lens 215. However,the transmission path of the radiant heat emitted from light source 221to dielectric lens 215 includes a transmission path from front cover 230a to dielectric lens 215 in addition to separator 214. Therefore, thelight apparatus U3 according to the present disclosure does notnecessarily have to have separator 214.

Further, in the above third to Embodiment 8, the headlight isillustrated as an example of the target to be applied of light apparatusU3, but light apparatus U3 according to the present disclosure can beapplied to a tail light, a small light or the like.

Further, in Embodiments 8, as an example of light apparatus U3, a modeof a horizontal type radar unit 210 using an end-fire array antenna isillustrated. However, light apparatus U3 according to the presentdisclosure can be applied not only to horizontal type radar unit 210 butalso to a vertical type radar unit.

In the above-mentioned Embodiment 8, an end-fire array antenna formed oncircuit board 211 is illustrated as an example of antenna 212 of radarapparatus 210. However, in the embodiment of the present invention, theconfiguration of antenna 212 is arbitrary, and may be made up of a Yagiarray antenna, a Fermi antenna, a post wall waveguide antenna, a postwall horn antenna, a horn antenna, or the like.

In Embodiment 8 described above, a mode in which three lamps 220 areprovided as an example of light apparatus U3 is described. However,light apparatus U3 according to the embodiment of the present inventionmay have only one lamp 220.

According to the control apparatus of the in-vehicle light apparatusaccording to an example of the present disclosure, decrease in radarperformance caused by ice, snow or the like adhering to the cover memberdisposed in front of the radar apparatus is suppressed.

The control apparatus according to an example of the present disclosureis an in-vehicle light apparatus control apparatus that integrallyincludes a lamp and a radar apparatus for monitoring a region in a firstdirection outside the vehicle, and includes: a reflected wave intensityacquirer for acquiring the intensity of the reflected wave of theelectromagnetic wave transmitted in the first direction by the radarapparatus; and a lighting controller configured to determine adhesion ofice, snow, or frost to a cover member disposed on the first directionside of the radar apparatus based on the intensity of the reflected waveand control the lamp to ON and OFF according to the result ofdetermination.

The control apparatus according to an example of the present disclosurefurther includes a weather information acquirer configured to acquireweather information at present at a travelling position of the vehicle,and the lighting controller is configured to determine adhesion of ice,snow, or frost to the cover member based on the intensity of thereflected wave and the weather information, and control the lamp to ONand OFF according to the result of determination.

In the control apparatus according to an example of the presentdisclosure, when the intensity of the reflected wave from the covermember is increased, the lighting controller turns the lamp ON forprocessing to increase the temperature of the cover member, and turnsthe lamp OFF when the intensity of the reflected wave from the covermember is reduced during the processing.

Embodiment 9

An antenna apparatus for radar configured to detect the position of anobject (hereinafter also referred to as “target”) in a non-contactmanner using an electromagnetic wave in a frequency band of millimeterwaves or microwaves.

This type of antenna apparatus is mounted on, for example, a vehicle ora ship. For example, Japanese Patent Application Laid-Open No.2008-186741 describes that the antenna apparatus is disposed in avehicle in an integral manner with a lamp that irradiates the outside ofthe vehicle. As another prior art document, Patent Application Laid-OpenNo. 62-090121 can be cited.

Incidentally, in this type of antenna apparatus, in general, from theviewpoint of protection from flying objects or the like, an antenna isdisposed in a cover member (for example, a bumper member of a vehicle),and the antenna is configured to transmit and receive an electromagneticwave via the cover member.

However, since the cover member is disposed with the front face exposedto the outside, water droplets, snow, raindrops, mud, dirt, or the likeon the front face of the cover member may adhere to the cover memberwhen the vehicle is driven in rainy weather. (Hereinafter referred to as“water droplets and the like”). Such water droplets and the like arefactors that greatly reduce the output gain and reception gain of theantenna apparatus.

In view of such problems described above, an example of the presentdisclosure provides an antenna apparatus and in-vehicle light apparatuscapable of suppressing the decrease in output gain and the decrease inreception gain due to water droplets and the like adhering to the frontface of the cover member.

An example of the configuration of antenna apparatus 310 according toEmbodiment 9 will be described with reference to FIG. 25 to FIG. 31.

In each drawing, in order to clarify the positional relationship of eachcomponent, a common orthogonal coordinate system based on the forwarddirection in which antenna apparatus 310 transmits an electromagneticwave to the outside apparatus (that is, the direction subject todetection of an object) (X, Y, Z). In the following description, a plusdirection of the X-axis represents the front direction in which antennaapparatus 310 transmits an electromagnetic wave to the outside theapparatus (hereinafter referred to as “forward direction”), a plusdirection of the Y-axis represents the left side direction side ofantenna apparatus 310 (hereinafter abbreviated as “leftward direction”)and a plus direction of the Z-axis represents upward of antennaapparatus 310 (hereinafter abbreviated as “upward direction”).

In the following description, +Z direction corresponds to the upward ofthe vehicle, and a direction about 30 degrees in the +Y direction from+X direction corresponds to the direction of travel of the vehicle.

FIG. 25 is a perspective view illustrating a state of installation inthe vehicle of antenna apparatus 310 according to Embodiment 9.

Antenna apparatus 310 according to Embodiment 9 is mounted on a vehicleand is disposed in an integral manner with lamps 320 a, 320 b, and 320 cthat irradiate the front of the vehicle. More specifically, antennaapparatus 310 according to Embodiment 9 is disposed adjacent to thelower sides of three lamps 320 a, 320 b, and 320 c arranged adjacent toeach other along the left-right direction, and constitutes in-vehiclelight apparatus U4 (here, vehicle headlight) together with lamps 320 a,320 b, and 320 c.

FIG. 26 is a sectional side view of antenna apparatus 310 according tothis embodiment. FIG. 27 is a drawing antenna apparatus 310 viewed fromabove according to this embodiment.

Antenna apparatus 310 according to Embodiment 9 is attached to the lowerside of lamp housing 330 storing lamps 320 a, 320 b, and 320 c by afixing member (for example, a screw member).

Lamp 320 a is formed of light source 321 a (for example, an LED lamp oran incandescent lamp) and a reflector 322 a which is disposed so as tosurround light source 321 a and condenses light so that the lightemitted from light source 321 a is directed forward. Lamps 320 b and 320c have the same configuration as lamp 320 a, and are each made up of thelight source and a reflector surrounding the light source.

Lamp housing 330 forms a storage space in the front end region of thevehicle, and stores lamp 320 a, 320 b, and 320 c in the storage space.Lamp housing 330 has front cover 330 a that covers the front face of thestorage space. Lamp housing 330 is made of, for example, a resinmaterial (for example, polycarbonate and the like). Further, front cover330 a is formed of, for example, a resin material (for example,polycarbonate and the like) having light permeability.

Antenna apparatus 310 includes circuit board 311, antenna 312, signalprocessing IC 313, radar housing 314, and dielectric lens 315.

Circuit board 311 is a board on which antenna 312 and signal processingIC 313 are mounted. As circuit board 311, for example, a Printed CircuitBoard (PCB), a semiconductor substrate with built-in signal processingIC 313, or the like is used.

Circuit board 311 is disposed such that the board surface extends in thelongitudinal direction, and typically, the board surface extends alongthe horizontal direction. Note that circuit board 311 is disposed on theupper side or lower side of lamps 320 a, 320 b, and 320 c in terms ofreduction in size of light apparatus U4 (in this example, the lowerside).

In other words, radar unit 310 constitutes a horizontal type millimeterwave radar in which circuit board 311 is disposed horizontally. As aresult, radar unit 310 is thinner than lamp unit 320 in the ±Zdirections.

Antenna 312 is disposed in the front area of the board surface ofcircuit board 311 and transmits electromagnetic wave Ft forward (+Xdirection), and receives reflected wave Fr which is the electromagneticwave reflected by a target.

Antenna 312 is, for example, an end-fire array antenna havingdirectional characteristics in the direction of the front end side ofcircuit board 311. The end-fire array antenna is configured to include aplurality of strip conductors which are arranged such that thelongitudinal direction thereof are in parallel, and transmits andreceives electromagnetic waves along the direction in which theplurality of strip conductors are arranged. Antenna 312 is composed of,for example, six end-fire array antennas (hereinafter also referred toas “antenna elements”) arranged adjacent along ±Y direction. Antenna 312is formed as a phased array antenna by six antenna elements.

For example, signal processing IC 313 transmits a high-frequency drivesignal to antenna 312 to cause antenna 312 to transmit anelectromagnetic wave (for example, an electromagnetic wave in amillimeter wave band), and perform reception processing of a receivedsignal relating to the reflected wave that antenna 312 has received.Then, detection of the distance to the target (for example, a vehicle ora person), the azimuth where the target is present, and the reflectionintensity and speed of the target and the like is performed by receptionprocessing (for example, detection wave processing or frequency analysisprocessing) by signal processing IC 313. Here, since the receptionprocessing by signal processing IC 313 is the same as a knownconfiguration, detailed description thereof is omitted here.

Radar housing 314 (corresponding to a “housing” in the presentdisclosure) accommodates circuit board 311 and supports dielectric lens315 in front of circuit board 311. Radar housing 314 typicallyaccommodates circuit board 311 in a substantially sealed state.

On the front face of radar housing 314, window portion 314 a fortransmitting and receiving electromagnetic waves between antenna 311 anda front region outside the vehicle is formed, and dielectric lens 315 isattached to window portion 314 a.

Examples of the material of radar housing 314 includes a metal materialor a resin material is used. When a resin material is used as radarhousing 314, radar housing 314 and dielectric lens 315 may be integrallyformed of the same resin material.

Dielectric lens 315 (corresponding to “cover member” in the presentdisclosure) is disposed such that the position of installation ofantenna 312, for example, is focused, narrows the beam of theelectromagnetic wave transmitted by antenna 312, transmits the sameforward, and condenses the reflected wave reflected by the target onantenna 312. Note that dielectric lens 315 is disposed with the frontface exposed to the outside of the vehicle, and also functions as acover member of antenna 312.

Dielectric lens 315 is, for example, formed of a semi-cylindrical orparabolic cylindrical lens, which protrudes in +X direction and extendsalong the ±Y direction. Dielectric lens 315 of the semi-cylindricalshape or the parabolic cylinder shape has substantially the same shapein side cross section at any position in ±Y direction, so that arefractive angle of the reflected wave reaching the different positionsin the ±Y direction can preferably be made to be the same. As a result,the reflected waves coming from the outside of the apparatus areprevented from entering antenna 312 from the various directions (forexample, +Y direction side −Y direction side with respect to antenna312). In other words, it is possible to prevent deterioration in theaccuracy of detection of an object (for example, deterioration inaccuracy due to mutual interference or deterioration in accuracy due toa change in phase difference).

FIG. 28 and FIG. 29 is an enlarged view illustrating a state of thefront face of dielectric lens 315.

Dielectric lens 315 has an irregular structure formed by a plurality ofprotrusions 315 a on the front face (that is, the surface exposed to theoutside). The irregular structure formed on the surface of the object isknown to change the surface free energy and retain water repellency onthe surface of the object (also referred to as the Lotus effect).Dielectric lens 315 of Embodiment 9 utilizes such a phenomenon. In otherwords, dielectric lens 315 according to Embodiment 9 is configured tohave a water repellent function on the front face by providing anirregular structure on the front face. Accordingly, when water adheresto the front face of dielectric lens 315, the water becomes waterdroplets and rolls down while entwining mud and other foreign matters.That is, the irregular structure acts to suppress adhesion of waterdroplets and the like to the front face of dielectric lens 315.

In addition, as an example of applying the Lotus effect, as in JapanesePatent Application Laid-Open No. 62-090121, there is widely known a fontcharacter that has improved water repellency by providing an irregularstructure on the surface. However, generally, if an irregular structureis provided on the surface of the resin arranged outside the millimeterwave radar, adverse effects such as changes in the beam direction of themillimeter wave radar and deterioration of reflection characteristicsmay occur.

In this regard, as described later, dielectric lens 315 according to thepresent disclosure has a characteristic in that an irregular structurethat can suppress the attachment of snow and water droplets to thesurface without causing degradation of the performance of the millimeterwave radar is employed.

The irregular structure formed on the front face of dielectric lens 315is, for example, formed by embossing dielectric lens 315. In addition,the method of forming the irregular structure is also arbitrary, forexample, the method of attaching protrusions 315 a on dielectric lens315 may be used.

Protrusions 315 a constituting the irregular structure has, for example,a dome shape (that is, a hemispherical shape). Size D1 of protrusions315 a (hereinafter, it represents the diameter of protrusion 315 a inplan view) is preferably as small as possible in terms of securing waterrepellency on the front face of dielectric lens 315 and in terms ofsuppressing lowering of the output gain and the reception gain ofantenna 312 and is typically set to 1000 μm at the maximum, and morepreferably, 100 μm as the maximum in plan view.

Note that size D1 of protrusions 315 a is preferably set based on thewavelength of the electromagnetic wave transmitted and received byantenna 312 when considering the influence on the output gain andreception gain of antenna 312. In particular, if size D1 of protrusions315 a is set to λ/40 or less (where is the free-space wavelength of theelectromagnetic wave transmitted and received by antenna 312) in planview, the decrease in output gain and decrease in reception gain causedby protrusion 315 a is almost negligible. The size of λ/40 correspondsto approximately 100 μm when the frequency of the electromagnetic wavetransmitted and received by antenna 312 is 80 GHz, and to approximately300 μm when the frequency of the electromagnetic wave transmitted andreceived by antenna 312 is 24 GHz.

FIG. 30 is a diagram illustrating a relationship between size D1 andreflectance (S11) of protrusions 315 a. In FIG. 30, the horizontal axisrepresents the frequency [Hz] of the electromagnetic wave transmittedfrom antenna 312 and the vertical axis represents reflectance (S11)[dB].

Each graph in FIG. 30 is obtained by calculating the size D1 andreflectance (S11) of protrusions 315 a by simulation by changing thefrequency of the electromagnetic wave transmitted from antenna 312.

Each graph in FIG. 30 represents the following.

-   -   Solid line graph: reflectance in a mode without protrusions 315        a    -   Dotted line graph: reflectance in a mode in which size D1 of        protrusions 315 a is 100 μm.    -   Dash-dotted line graph: reflectance in a mode in which size D1        of protrusions 315 a is 300 μm.    -   Dashed-two dotted line graph: reflectance in a mode in which the        size D1 of protrusions 315 a is 1000 μm.

As can be seen from FIG. 30, when size D1 of protrusion 315 a is 100 μmor less, there is no great difference in the reflection characteristicsof protrusions 315 a between the mode with protrusion 315 a and the modewithout protrusions 315 a. Therefore, if size D1 of protrusions 315 a is100 μm or less, it can be said that the decrease in output gain andreception gain caused by passing through protrusions 315 a can besuppressed.

FIG. 31 is a diagram illustrating the relationship between size D1 ofprotrusions 315 a and the antenna gain of antenna 312. In FIG. 31, thehorizontal axis represents the angle of the electromagnetic wavetransmitted from antenna 312 (the position of 90 degrees corresponds to+X direction), and the vertical axis represents the antenna gain inantenna 312.

Each graph in FIG. 31 is obtained by changing the direction of theelectromagnetic wave transmitted from antenna 312 (here, 80 GHzelectromagnetic wave), and calculating the wave intensity (that is,antenna gain) of the reflected wave from the predetermined target, whichis received by antenna 312 for each direction, by simulation.

Each graph in FIG. 31 represents the following.

-   -   Solid line graph: antenna gain in a mode without protrusions 315        a    -   Dotted line graph: antenna gain in a mode in which the size D1        of protrusions 315 a is 100 μm.    -   Dash-dotted line graph: antenna gain in a mode in which the size        D1 of protrusions 315 a is 300 μm.    -   Dashed-two dotted line graph: antenna gain in a mode in which        the size D1 of protrusions 315 a is 1000 μm.

As can be seen from FIG. 31, as size D1 of protrusions 315 a increases,the half power beam width (HPBW) (here, the half power beam width of 3dB) becomes narrower than that in the beam half width. The beam halfwidth in each mode is as follows.

-   -   The beam half width in a mode without protrusions 315 a: and 103        degrees.    -   The beam half width in a mode in which the size D1 of        protrusions 315 a is 100 μm: 103 degrees.    -   The beam half width in a mode in which the size D1 of        protrusions 315 a is 300 μm: 102 degrees.    -   The beam half width in a mode in which the size D1 of        protrusions 315 a is 1000 μm: 102 degrees.

From this result, in the case where size D1 of protrusions 315 a is setto 100 μm or less, the radar performance equivalent to that in the casewithout protrusion 315 a can be ensured. Note that, when size D1 ofprotrusion 315 a is set to 300 μm to 1000 μm, the radar performance isnot as good as the case where the size of protrusions 315 a is 100 μm,but the reflection characteristic is sufficient for achieving thefunction of detection of an object.

Effect of One Example

As described above, antenna apparatus 310 of Embodiment 9 includes:radar housing 314; antenna 312 stored in radar housing 314 andconfigured to transmit an electromagnetic wave to the front through thewindow portion formed on the front face of radar housing 314 and receivethe reflected wave; and cover member (dielectric lens in Embodiment 9)315 disposed at the window portion of radar housing 314 and having theirregular structure on the front face.

Therefore, according to antenna apparatus 310 of Embodiment 9, adhesionof water droplets or the like (for example, snow, raindrops, mud, dirt,or the like) to the front face of cover member (dielectric lens inEmbodiment 9) 315 may be suppressed by a Lotus effect of the pluralityof protrusions 315 a. In other words, adhesion of water droplets or thelike to the vicinity of a radar aperture surface can be suppressed.Accordingly, decrease in output gain and decrease in reception gaincaused by water droplets may be suppressed.

In particular, in antenna apparatus 310 according to Embodiment 9,dielectric lens 315 is mounted on the vehicle such that the front facethereof is exposed to the outside, and dielectric lens 315 alsofunctions as a cover member for protecting antenna 312. Accordingly,antenna 312 can transmit and receive electromagnetic waves to and fromthe outside without interposing any member other than dielectric lens315, and when transmitting and receiving electromagnetic waves inantenna apparatus 310, decrease in output gain or decrease in receptiongain caused by water droplets or the like can be suppressed.

In particular, antenna apparatus 310 according to Embodiment 9 is formedas in-vehicle light apparatus U4 integrally with lamps 320 a, 320 b, and320 c. Therefore, the space for installation when mounting on is saved,which contributes to improvement in the design of the vehicle body.

Embodiment 10

Next, antenna apparatus 310 according to Embodiment 10 will be describedwith reference to FIG. 32. Antenna apparatus 310 according Embodiment 10is different from Embodiment 9 in that a plurality of protrusions 315 ahaving different sizes are formed on the front face of dielectric lens315. Note that description of the structure in common with Embodiment 9is omitted. (hereinafter, the same applies to the other embodiments).

FIG. 32 is a sectional side view illustrating an example of theconfiguration of antenna apparatus 310 according to Embodiment 10.

Dielectric lens 315 according to Embodiment 10 includes with firstprotrusions 315 aa (protrusions 315 a of size D1 in FIG. 32), and secondprotrusions 315 ab (protrusions 315 a of the size D2 in FIG. 32) whichis smaller in size than first protrusion 315 aa on the front facethereof.

Accordingly, the azimuth or frequency at which the output gain decreasescaused by protrusions 315 a can be dispersed from the specific azimuthand the specific frequency. Therefore, generation of a blind spot areain which detection of an object is impossible is suppressed, so thatmore preferable radar performances are achieved.

Although only two sizes are exemplified as the size of protrusions 315a, protrusions 315 a having three or more different sizes may beprovided. The size of protrusions 315 a is also arbitrary.

Embodiment 11

Next, antenna apparatus 310 according to Embodiment 11 will be describedwith reference to FIG. 33. Antenna apparatus 310 according to Embodiment11 is different from Embodiment 9 in that planar cover member 317,instead of dielectric lens 315, is disposed in front of antenna 312.

FIG. 33 is a sectional side view illustrating an example of theconfiguration of antenna apparatus 310 according to Embodiment 11.

Cover member 317 according to Embodiment 11 is formed into a planarshape and has no function as a dielectric lens. However, similarly todielectric lens 315 described in Embodiment 9, cover member 317according to Embodiment 11 has an irregular structure on the front face.The irregular structure of cover member 317 is formed by a plurality ofprotrusions 317 a as well as the irregular structure of dielectric lens315 as described, for example, in Embodiment 9. Cover member 317 has awater repellent function on the front face thereof by the irregularstructure.

Cover member 317 of Embodiment 11 has the front face having a shape inwhich an upper region is protruded forward than a lower region.Accordingly, water droplets or the like adhering to the front face ofcover member 317 can be dropped to the lower side of cover member 317more effectively.

Although Embodiment 11 has been described about a case of a planarshape, the present invention is not limited thereto, and a similareffect can be expected as long as the shape is such that at least theupper region protrudes toward forward than the lower region.

(Modified Modes)

The embodiments of the present invention are not limited to Embodiments9 to 11 described above, and various modified modes are alsoconceivable.

In Embodiments 9 to 11 described above, various examples of theconfiguration of the light apparatus U4 have been described. However, itis needless to say that a combination of modes described in therespective embodiments may also be used.

In Embodiments 9 to 11 described above, semi-cylindrical lens isillustrated as an example of the shape of dielectric lens 315. However,examples of the shape of dielectric lens 315 include a dome-type lens, adouble-sided convex lens, a ball lens, a Fresnel lens, or a combinationthereof, or a concave lens and a combination thereof. In addition, asdielectric lens 315, a concave lens that diffuses an electromagneticwave transmitted from antenna 312 may be applied.

In Embodiment 9 to 11 described above, the irregular structure formed ofdome-shaped protrusions 315 a is formed on the front face of dielectriclens 315 has been exemplified. However, the shape of protrusions 315 aconstituting the irregular structure is arbitrary, and may be formed bystriped protrusions 315 a instead of dome-shaped protrusions 315 a. Inthis case, the size of protrusions 315 a may be set to 1000 μm or lesswith reference to a longest distance between both ends of protrusions315 a in plan view. Note that even when the configuration or thestructure of antenna 312 or is changed specifically if the size is setto 100 μm or less, the influence on the antenna performance due to theirregular structure is negligible as a matter of course. However, inEmbodiments 9 to 11 described above, the irregular structure ofhemispherical shape has been described as an example. However, thepresent invention is not limited thereto, and the irregular structuremay be any shape that can be expected to have a water-repellent effectwith a size that does not cause degradation in performance of amillimeter wave radar, such as an elliptical shape, a rectangular shape,a triangular shape, or the like.

In Embodiments 9 to 11 described above, an end-fire array antenna isillustrated as an example of an antenna element constituting antenna312. However, antenna 312 only needs to be made up of a conductorpattern formed on circuit board 311, and instead of the end-fire arrayantenna, a Yagi array antenna, a Fermi antenna, a post wall waveguideantenna, or a post wall horn antenna or the like are also applicable.

In Embodiments 9 to 11 described above, modes in which antenna apparatus310 applied to in-vehicle light apparatus U4 have been described as anexample of antenna apparatus 310. However, antenna apparatus 310according to the embodiments of the present invention may be applied tothose other than the in-vehicle light apparatus U4, and may be disposedsolely at the position of, for example, a bumper member of the vehicle.

According to the antenna apparatus of one example of the presentdisclosure, it is possible to suppress decrease in output gain anddecrease in reception gain caused by water droplets or the like adheringto the front face of the cover member.

An antenna apparatus according to an example of the present disclosureincludes:

a housing; an antenna stored in the housing and configured to transmitan electromagnetic wave to the front through the window portion formedon the front face of the housing and receive the reflected wave thereof;and a cover member disposed on the window portion of the housing andhaving an irregular structure on a front face thereof.

According to the antenna apparatus of an example of the presentdisclosure, the irregular structure is formed by a plurality ofprotrusions provided on the front face of the cover member.

According to the antenna apparatus of an example of the presentdisclosure, the plurality of protrusions each have a dome shape.

According to the antenna apparatus of an example of the presentdisclosure, a diameter of each of the plurality of protrusions is 1000μm or less in plan view

According to the antenna apparatus of an example of the presentdisclosure, the diameter of each of the plurality of protrusions issubstantially λ/40 (λ, is the free-space wavelength of theelectromagnetic wave) in plan view.

According to the antenna apparatus of an example of the presentdisclosure, the plurality of protrusions includes a first protrusion anda second protrusion having sizes different from each other.

According to the antenna apparatus of an example of the presentdisclosure, the cover member is a dielectric lens that condenses ordiffuses the electromagnetic wave transmitted from the antenna.

According to the antenna apparatus of an example of the presentdisclosure, a front portion of the dielectric lens has asemi-cylindrical shape or parabolic cylindrical shape protruding towardthe front.

According to the antenna apparatus of an example of the presentdisclosure, wherein the front face of the cover member is shaped suchprotruding forward in an upper region than in a lower region.

According to the antenna apparatus of an example of the presentdisclosure, the antenna includes an end-fire array antenna disposed on acircuit board.

According to the antenna apparatus of an example of the presentdisclosure, the antenna includes the plurality of end-fire arrayantennas arranged in an array along a direction orthogonal to theforward direction.

According to the antenna apparatus of an example of the presentdisclosure, the cover member is mounted on the vehicle with a front faceexposed to the outside.

The in-vehicle light apparatus according to an example of the presentdisclosure includes the antenna apparatus described above.

While specific examples of the present invention have been described indetail above, these are merely examples and are not intended to limitthe scope of the claims. Technologies described in the appended claimsinclude various modified modes and changed modes of the examplesillustrated above.

In addition, while various embodiments have been described herein above,it is to be appreciated that various changes in form and detail may bemade without departing from the sprit and scope of the invention(s)presently or hereafter claimed.

This application is entitled and claims the benefit of Japanese PatentApplication No. 2018-183699, filed on Sep. 28, 2018, Japanese PatentApplication No. 2018-183702, filed on Sep. 28, 2018, Japanese PatentApplication No. 2018-183711, filed on Sep. 28, 2018 and Japanese PatentApplication No. 2018-183715, filed on Sep. 28, 2018, the disclosure ofwhich including the specification, drawings and abstract is incorporatedherein by reference in its entirety.

INDUSTRIAL APPLICABILITY

According to an in-vehicle light apparatus according to an example ofthe present disclosure, it is possible to suppress deterioration ofradar performance caused by multiple reflections with an integratedradar and lamp configuration.

REFERENCE SIGNS LIST

-   U1 in-vehicle light apparatus-   10 radar unit-   11 circuit board-   12 antenna-   13 signal processing IC-   20 a, 20 b, 20 c lamp unit-   21 a, 21 b, 21 c light source-   22 a, 22 b, 22 c reflector-   30 housing-   30 a front cover-   40 garnish material-   40 a lens-   U2 in-vehicle light apparatus-   110 radar unit-   111 circuit board-   112 antenna-   113 signal processing IC-   114 separator-   114 a first extending portion-   114 b second extending portion-   114 c third extending portion-   114 d electromagnetic wave absorbing material-   115 dielectric lens-   120 a, 120 b, 120 c lamp unit-   121 a, 121 b, 121 c light source-   122 a, 122 b, 122 c reflector-   130 lamp housing-   130 a front cover-   U3 in-vehicle light apparatus-   210 radar apparatus-   211 circuit board-   212 antenna-   213 signal processing IC-   214 separator-   215 dielectric lens (cover member)-   220 a, 220 b, 220 c lamp-   221 a light source-   222 a reflector-   230 lamp housing-   230 a front cover-   200 ECU-   201 reflected wave intensity acquirer-   202 weather information acquirer-   203 lighting controller-   U4 in-vehicle light apparatus-   310 antenna apparatus-   311 circuit board-   312 antenna-   313 signal processing IC-   314 radar housing-   315 dielectric lens-   315 protrusions-   317 cover member-   320 a, 320 b, 320 c lamp-   321 a light source-   322 a reflector-   330 lamp housing-   330 a front cover

1. A light apparatus mounted on a vehicle comprising: a lamp that emitslight into a first region through a first cover; and a radar provided ona lower side or an upper side of the lamp, wherein the radar includes: aseparator provided between the lamp and the radar, a circuit boardhaving a board surface arranged in a substantially horizontal manner;and an antenna that is disposed on the board surface of the circuitboard, transmits electromagnetic waves through a second cover in asecond region that is at least partially different from the firstregion, and receives reflected waves through the second cover fromobjects outside the vehicle in the second region.
 2. The light apparatusaccording to claim 1, wherein the separator is in contact with at leastone of the second cover and the first cover.
 3. The light apparatusaccording to claim 1, wherein the circuit board is covered with theseparator and the second cover, and a portion of the separator opposedto the second cover is inclined relative to the circuit board.
 4. Thelight apparatus according to claim 1, wherein the circuit board iscovered with the separator and the second cover, and a height of a partof the separator opposed to the second cover is lower than a height ofthe separator near the second cover.
 5. The light apparatus according toclaim 1, wherein the second cover has a plurality of dome-shapedprojections provided at an outer side thereof.
 6. The light apparatusaccording to claim 5, wherein a diameter of each of the plurality ofdome-shaped projections is 1000 μm or less.
 7. The light apparatusaccording to claim 5, wherein a diameter of each of the plurality ofdome-shaped projections is λ/40 or less, and the λ is a free spacewavelength of the electromagnetic wave.
 8. The light apparatus accordingto claim 5, wherein among the plurality of dome-shaped projections,adjacent dome-shaped projections have different diameters.
 9. The lightapparatus according to claim 1, wherein the antenna is an end-fire arrayantenna.